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Rytting, B.M., Harper, M.R., Edmond, K.V., Zhang, Y., Kilpatrick, P.K., 2019. High-purity vanadyl petroporphyrins: Their aggregation and effect on the aggregation of asphaltenes. Energy &Fuels 34, 164-178.

https://doi.org/10.1021/acs.energyfuels.9b03237 Small-angle neutron scattering (SANS) is used to characterize the aggregation of pure vanadyl petroporphyrins (VOPPs), as well as of asphaltenes mixed with either VOPPs or synthetic porphyrins. Simple VOPPs generally form small nanoaggregates, likely dimers and trimers, and have low solubility in toluene and form precipitates. More-complex VOPPs can form large, asphaltene-like nanoaggregates in toluene. Less-functionalized porphyrins are shown to inhibit asphaltene aggregation. More-functionalized porphyrins, potentially having one or more intermolecular interaction sites outside of the central macrocycle, have a tendency to promote aggregation and/or flocculation of asphaltenes at lower temperatures, but have little or no effect at or above room temperature. Highly functionalized porphyrins (petroleum-based and synthetic) are also shown to facilitate asphaltene aggregation, either through the formation of larger nanoaggregates or flocculation, while simpler porphyrins have a tendency to inhibit asphaltene self-assembly.

Sahai, N., Schoonen, M.A., 2019. Accuracy of thermodynamic databases for hydroxyapatite dissolution constant. Astrobiology 20, 157-160.

https://doi.org/10.1089/ast.2019.2158 Discrepancies have been noted in the solubility constant values of calcium phosphate minerals between various databases employed in widely used aqueous speciation calculation software programs. This can cause serious errors in the calculated speciation of waters when using these software programs. The aim of this communication was to bring to light these discrepancies. Experimental determinations of the hydroxyapatite (HAP) solubility product vary by as much as 10 orders of magnitude as a result of experimental challenges related to the presence of impurities in the HAP used, incongruent dissolution, and the contamination of solutions with dissolved carbon dioxide. It is suggested that the value used in the database Thermo.dat is consistent with experimental data devoid of common experimental problems, whereas other common databases use values that lead to a vastly overestimated solubility of HAP.

Saini, R., Hegde, K., Brar, S.K., Vezina, P., 2020. Advanced biofuel production and road to commercialization: An Rhodosporidium insight into bioconversion potential of sp. Biomass and Bioenergy 132, 105439.